what is the range of f?

Answer:
Range is [tex]-5 \le y \le 5[/tex]
Range in interval notation is [-5, 5]
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Explanation:
Refer to the diagram below. As marked in red, the smallest y value is y = -5. The largest y value is y = 5. The range is the set of y values between these endpoints, including both endpoints.
We can say the range is [tex]-5 \le y \le 5[/tex]
In interval notation, we write that as [-5, 5]. The use of square brackets tells the reader that the endpoints are included as part of the range.